foo.cpp: In function 'int main()':
foo.cpp:15:1: error: 'cin' was not declared in this scope
 cin>>a>>b;
 ^
foo.cpp:15:1: note: suggested alternative:
In file included from foo.cpp:3:0:
c:\mingw\lib\gcc\mingw32\4.8.1\include\c++\iostream:60:18: note:   'std::cin'
   extern istream cin;  /// Linked to standard input
                  ^
foo.cpp:16:1: error: 'cout' was not declared in this scope
 cout<<a*b;
 ^
foo.cpp:16:1: note: suggested alternative:
In file included from foo.cpp:3:0:
c:\mingw\lib\gcc\mingw32\4.8.1\include\c++\iostream:61:18: note:   'std::cout'
   extern ostream cout;  /// Linked to standard output
                  ^